Document Store validates `schema_version` if it is submitted with the record via HTTP POST/PUT. It does not validate `schema_version` when it itself responds with a record payload. Kuha Common support for changing the `schema_version` is under development (see https://gitlab.tuni.fi/fsd/kuha_common/-/issues/66). Require Kuha Common that supports changing the schema_version and build a process for handling minor-version changes when updating records to DocStore. --- ## Minor Version Change A minor version change does **not** introduce breaking changes, it requires no migrations, but records must be re-synced. An example of a minor change: a new attribute is introduced to records schema. Processing plan draft: 1. Client checks docstore record schema versions and compares them to ones it recognises. 2. If they differ, all records must be updated. Cache will be invalidated (see #28). 3. Iterate all XML files and update records accordingly. Soft-remove records not included in the batch. This step is business as usual. 4. Iterate all docstore records with an invalid schema version. At this point they should all be soft deleted. 5. Update the schema version and `HTTP PUT` the record back.